Temperature and Current Dependent Capture of Injected Carriers in InGaN Single-Quantum-Well Light-Emitting Diodes

Abstract

Temperature and injection current dependence of electroluminescence (EL) spectral intensity of the super-bright InGaN single-quantum-well (SQW) light-emitting diodes (LEDs) has been carefully investigated over a wide temperature range (T = 15–300 K) and as a function of injection current level (0.1–10 mA). It is found that, when T is slightly decreased from 300 to 140 K, the EL intensity efficiently increases due to reduced non-radiative recombination processes. However, with further decrease of T below 100 K, it drastically decreases due to the reduced carrier capturing by the localized radiative recombination centers and shows a clear trend of saturation with current, accompanying decreases of the EL differential efficiency. These results are analyzed based on a rate equation model, assuming a finite number of radiative recombination centers.